Safety mechanism for hoisting apparatus.



' UNITED STATES PATENT OFFICE.

JOHN HENRYYPIOKAVANCE, OF JOHANNESBURG, TRANSVAALQ SAFETY MECHANISM FOR HOISTING APPARATUS.

Specification of Letters Patent Patented March 13, 1906.

Application filed December 21, 1904. Serial No. 237,820.

in Safety Mechanism for Hoisting Apparatus of which the following is a specification.

This invention relates to safety appliances or mechanism applicable for the skips or cages employed in the shafts of mines for hoists, lifts, elevators, or similar ap aratus in which a skip, cage, bucket, or the ike is'hoisted or hauled by means of a rope and said skip, cage, or bucket traverses guides, rails, runners, or their equivalent in the shaft of the mine or well of the hoist or elevator.

Now the object of the present invention is to utilize the energy of the unsu ported and falling load to operate the catc or safetygear to bring the skip, cage, or bucket to rest should it become detached from the haulingrope or be unsupported thereby from any ot er cause or to insure that the energy of the falling load will be utilized to work with the safety-gear and not against it.

In order that theinvention may be more readily understood, I append an' explanatory sheet of drawings.

Figure 1 shows the invention in side elevation. Fig. 2 illustrates it in end elevation, or

' is a view taken at right angles to Fig. 1; and

Fig. 3 is a sectional plan on line any of Fig. 1.

The skip, cage, bucket, or its equivalent is represented at A. It is, as shown, carried by or supported inan inner frame B, which lat,- 'ter is arranged within an outer frame C, the latter being constructed to traverse the guides or runners D E at opposite sides of the shaft of the mine, the well of the lift, or the like. The outer rectangular frame 0 comprises the top horizontal member 0, the two vertical side members 0' c and the bottom horizontal member 0 The two vertical members 0 c of the frame 0 are constructed with flanges or projections c, whichproject to either side of.

the guide-rails or runners D E, and so operate to guide the skip, cage, or bucket A as it traverses up and down the shaft or well. The

vertical members 0 c of the outer frame C their extremities project to either side of the in Fig. 2 of the drawings.

On each end of each of the two horizontally-disposed rods or spindles c are keyed or otherwise'securely fixed the catches F, one at either side of each of the guides or runners D E. The catches F at their lower extremities f are constructed so that they will penetrate the sides of the guides or runners to arrest the movement of the skip, cage, or bucket should guides or runners D E, as is clearly illustrated the latter become unsupported in the shaft or I well. In the normal working of the hoisting apparatus that is to say, when the skip, cage, bucket, or the like is suspended in the shaft and su ported by the haulingrope. the catches F run clear of the guides or runners D E. The manner in which they are operated will be hereinafter fully explained.

The inner frame B comprises the to horizontal member I), the two' vertical an oppositely-arranged side members 1) b and the.

bottom horizontal member b The two side members I) b of the inner frame B are constructed with flanges or projections b 1n roximity to the upper and lower ends 0 'said members which project to the outside of the flanges c ,'formed on the vertical members 0 c of the outer frame C, By this means the inner frame B is prevented moving except vertically inside the outer frame G.

The vertical members I) b of the inner frame B at their lower ends are formed with lugs or projections 6 in which holes are formed to receive the rods G, which form rests for the bottom of the skip, cage, or bucket A. The means for supporting the skip, cage, or bucket A in the frame form no feature of the present invention, and they may be of any desired form or construction.

The vertical members I) b of the inner frame B at or in proximity to their upper ends are constuct ed at each side of the runners DE with lugs or enlargements I), in which are provided bearings for two horizontally-arranged rods or spindles H.

On each of the two horizontally-arranged rods or spindles H are loosely mounted two links h, one ateither end, and on each of the two horizontally-disposed rods or'spindles 0, carried by the outer frame 0, are keyed or otherwise securelyfixed two rock-arms h, one in proximity to each endf The outer ends of the rock-arms h are pivotally attached to the upper ends of the links h.

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the outer frame C and the top horizontal member 6 of the inner frame B are located two suitable helical springs J. K represents cylindrical projections formed on or fixed to the two horizontal members I) c, which project for a suitable distance between the coils of the springs J and. serve to maintain the latter in correct position between said horizontal members 0 The draw-bar L is free to move up and down through a hole Z, formed in the top horizontal member 0 at the center. The lower extremity of the draw-bar L projects through a hole Z in the top horizontal member I) of the inner frame B, in which it is secured by means of the nut Z and check-nut Z screwed on the end of the draw-bar L beneath said horizontal member I). On the .drawbar L is formed a collar or enlargement Z, which engages the under side of the top horizontal member 0, which collar Z operates to prevent the inner frame B being raised inside the outer frame C beyond a certain point in the normal working of the skip, cage, or bucket in the shaft or well. In the draw-bar L above the top horizontal member a is formed a hole Z ,which provides means for putting the safety-gear out of operation by placing in said hole Z a pin or key, which by engaging the top of the horizontal member 0 prevents the draw-bar L falling inside the outer frame C. Mis a shackle or means for attaching the haulingrope to the upper extremity of the draw-bar L. This may be of any preferred construction The action of the mechanism will now be readily understood and may be shortly described as follows: In the event of haulingrope breaking or of the skip, cage, or bucket A or the like becoming unsupported by the rope from any other cause the draw-bar L by virtue of its weight, assisted by the spiral springs J and the weight of the unsupported skip, cage, or bucket A, will fall down inside the outer frame 0, and the inner frame B be ing thus permitted to fall inside the outer frame C will draw down with it the links it. The downward movement of the links 7t will rotate the rock-arms h, and with them the rods or spindles c. The rotation of the rods or spindles 0 will bring the lower extremities f of the catches F into engagement with the sides of the guides or runners D E, whereupon the catches F will penetrate said guides or runners, and so bring the skip, cage, bulclket, or equivalent to rest in the shaft or we In the accompanying drawin s my invention is shown, by way of example, applied to wooden guides or runners and adapted to operate catches to penetrate said wooden guides to arrest the movement of the skip, cage, or bucket. It will be evident that the invention is equally applicable to safety-gear, in which the catches are arranged to be brought into engagement with teeth, projections, notches, or recesses formed in the guides or runners.

What I claim as my invention, and desire to protect by Letters Patent, is

1. Safety mechanism for hoisting apparatus comprising in combination, an outer frame adapted to traverse the guides of the shaft, spindles journalod in said frame on each side of the guides, catches fixed on said spindles, an inner frame adapted to slide in the outer frame, rods supported in said inner frame, connections between the spindles in the outer frame and the rods in the inner frame which operate the catches when the inner frame falls inside the outer frame, and means for effecting said falling movement of the inner frame when said inner frame becomes unsupported, substantially as described.

2. Safety mechanism for hoisting apparatus, comprising in combination, an outer frame adapted to traverse the guides of the shaft, spindles journaled in said frame at each side of the guides, catches fixed on said spindles at each side of the guides, rock-arms fixed on said spindles, an inner frame adapted to slide on the outer frame, rods supported in said inner frame, links loosely mounted 011 said rods and loosely pivoted at their other ends to the rock-arms fixed on the spindles carried by the outer frame, and springs interposed between the frames which operate to cause relative movement of the frames in the event of said inner frame becoming unsupported to operate the catches, substantially as described.

3. Safety mechanism for hoisting apparatus comprising in combination, an outer frame having flanges adapted to traverse the guides of the shaft, two horizontally-arranged spindles journaled in bearings in the upper end of the frame, one at each side of said guides, catches fixed on the extremities of said spindles at each side of the guides, rock-arms fixed on said spindles at each end, an inner frame constructed with flanges adapted to traverse the sides of the outer frame, two horizontally-arranged rods supported in the upper end of said inner frame, links loosely mounted on each end of each of said horizontal rods, said links being attached at their other ends to the rock-arms fixed on the horizontal spindles carried by the outer frame, springs arranged between the top horizontal members of the two frames which serve to cause the inner frame to fall inside the outer frame when said said guides, two horizontally-arranged spindles journaled in said bearings, a pair of rockarms fixed on each spindle, one at each end, a pair of catches fixed on each of said spindles,

5 .one at each extremity outside the outer frame and adapted to engage the guides, said outer frame having flanges and adapted to traverse the guides and formed with a hole in the top horizontal member through which I I the draw-bar works, the draw-bar, an inner frame having flanges adapted to traverse the vertical members of the outer frame, constructed at its lower end to support the bucket or the like and having lugs which I 5 form bearings at each side of the guides, two

horizontally-disposed rods supported in saidbearings, a pair of links loosely mounted on each rod, one at each end, said links being pivotally attached at their upper ends to the 20 outer ends of the rock-arms, the top horizontal member of said inner'frame having a ,hole through which "the lower end of the draw-bar projects and in which it is secured, the draw-bar havin a collar which by engaging tne top horlzontal member of the outer frame prevents the innerframe rising 1n the outer frame beyond a certain point, and a pair of spiral springs located between the top horizontal members of the two frames,

and the two cylindrical projections on said top horizontal members to maintain said JOHN HENRY PICKAVANOE.

Witnesses CHAS. OVENDALE, I R. OVENDALE. 

